Why Your Well Pump Keeps Running and Won’t Shut Off
Quick Answer: A well pump that runs constantly means it can't reach the pressure that tells it to stop — or something keeps draining that pressure. The usual causes are a leak somewhere (a running toilet, a leaking drop pipe, or a break in the line), a failed pressure switch, a waterlogged pressure tank, a worn pump that can't build pressure, a dropped water level, or a pump that has lost its prime. Running nonstop overheats and wears out the pump, so shut it off and have it diagnosed.
A well pump is supposed to cycle: it runs, builds pressure, and shuts off until you use water again. When it just keeps running and never clicks off, something has broken that loop — either the pump can't reach its cutoff pressure, or water is escaping as fast as it's pumped. It's worth acting quickly, because a pump running around the clock overheats and wears out fast. Here's what's usually behind it.
How the System Is Supposed to Work
Your well system runs on pressure. The pump fills a pressure tank until a pressure switch senses it's reached the cutoff point, then shuts the pump off. As you use water, pressure drops until the switch turns the pump back on. A pump that never shuts off means that the cycle is broken: either it can't build enough pressure to hit the cutoff, or pressure is leaking away the moment it's made. Almost every cause falls into one of those two buckets.
The Common Causes
A Leak Somewhere in the System
This is one of the most common reasons. If water is escaping — a running or leaking toilet, a leaking fixture, a crack in the drop pipe down the well, or a break in a buried line — the pump keeps running, trying to keep up with the loss, and never reaches cutoff pressure. A toilet that runs constantly is a frequent and easily overlooked culprit. The tell is that the pump runs even when no one is using water on purpose.
A Failed Pressure Switch
The pressure switch is the brain that tells the pump when to stop. If it fails or its contacts stick, the pump may never get the signal to shut off. A bad switch is a common, relatively simple cause of a pump that won't cycle off.
A Waterlogged Pressure Tank
A pressure tank uses a cushion of air to maintain pressure. If that air charge is lost (a "waterlogged" tank), the tank can't hold pressure properly, so the pump short-cycles or runs excessively trying to compensate. A tank that's lost its air charge is a frequent cause of pump behavior problems.
A Worn-Out Pump
A pump that's aging or worn may simply no longer be able to build enough pressure to reach the cutoff point, so it runs and runs without ever getting there. This often shows up alongside weak pressure throughout the house.
A Dropped Water Level or Lost Prime
If the water level in the well drops below the pump (from drought, heavy demand, or a well issue), or the pump loses its prime, it can run without delivering water — pumping air or struggling to draw water, never building pressure. This can also pull in air and sediment.
| What you notice | Likely cause | What it points to |
|---|---|---|
| Pump runs with no water in use | Leak (toilet, pipe, drop pipe) | Find and repair the leak |
| Pump never clicks off | Failed pressure switch | Replace the switch |
| Pump short-cycles or runs a lot | Waterlogged pressure tank | Recharge or replace the tank |
| Runs constantly, weak pressure | Worn-out pump | Pump service or replacement |
| Runs but little/no water | Dropped water level/lost prime | Well and pump diagnosis |
What to Do
Start with the easy check: rule out a running toilet or an obvious leaking fixture, since a constantly running toilet is a common and simple fix. Beyond that, a pump that won't shut off shouldn't be left running — continuous operation overheats the motor and accelerates wear and can burn the pump out. It's best to shut the pump off at the breaker if it's clearly running nonstop and have the system diagnosed.
A well professional can quickly narrow it down: testing the pressure switch, checking the pressure tank's air charge, looking for leaks in the system and drop pipe, and assessing the pump and water level. Because the causes range from a cheap switch to a worn pump or a well-level issue, getting it diagnosed is what tells you whether it's a small repair or a bigger one — and it protects the pump from running itself to failure in the meantime.
Frequently Asked Questions
Yes. A pump that runs nonstop overheats and wears out far faster than one that cycles normally, and it can burn out the motor. It also signals an underlying problem — a leak, a failed switch, a waterlogged tank, or a worn pump. If your pump is clearly running constantly, it's best to shut it off at the breaker and have the cause diagnosed before the pump is damaged.
That almost always means water is escaping somewhere, so the pump never reaches its cutoff pressure. The most common hidden culprit is a running or leaking toilet, but it can also be a leaking fixture, a cracked drop pipe in the well, or a break in a buried line. A failed pressure switch that won't signal the pump to stop can also cause it. Start by checking for a running toilet.
A pressure tank holds a cushion of air that maintains water pressure. When that air charge is lost, the tank becomes "waterlogged" and can't hold pressure properly, so the pump cycles too often or runs excessively trying to keep up. It's a common cause of pump behavior problems and is addressed by recharging the tank's air or replacing the tank if its bladder has failed.
Yes. The pressure switch tells the pump when to shut off, so if it fails or its contacts stick, the pump may never get the signal to stop and will keep running. A failed pressure switch is a common and relatively simple cause of a pump that won't cycle off, and replacing it often restores normal operation — though it should be confirmed against other causes like leaks or tank issues.
If the pump runs but delivers little water, the water level in the well may have dropped below the pump, or the pump may have lost its prime — so it's pumping air or struggling to draw water without building pressure. A worn pump that can no longer build pressure does the same. These need a professional to check the water level, the pump, and the system, since the fix depends on the cause.
Don't Let It Run Itself to Death
A well pump that won't shut off is telling you the pressure loop is broken — water is leaking away, or the pump can't reach the cutoff. Rule out a running toilet first, but if it keeps running, shut it off at the breaker so it doesn't overheat and burn out, and get it diagnosed. The cause might be as small as a pressure switch or as significant as a worn pump or a dropped water level, and the only way to know is to properly look at the system.
Well pump running nonstop? — Get the leak, switch, tank, or pump diagnosed before the motor burns out. Perry-Pump Repair Service LLC serves Lake Butler, Gainesville, Alachua. Call (352) 474-7142.
